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How to modify the oracle table name

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2023-04-21 11:19:593395browse

Oracle is a popular relational database management system (RDBMS) used by many enterprises to store and manage data. In the actual use of Oracle, it is often necessary to modify existing table names. Although Oracle does not encourage frequent modification of table names, it is still necessary from time to time. This article will introduce how to modify the table name in the Oracle database.

  1. The basic syntax for modifying the table name

In Oracle, the basic syntax for modifying the table name is as follows:

ALTER TABLE old_table_name RENAME TO new_table_name;

Among them, "old_table_name" is the The modified original table name, "new_table_name" is the new table name. To execute this statement, you must have "ALTER TABLE" permission.

For example, let's say we have a table named "employees" and now we want to rename it "staff". Then we need to enter the following command in the SQL tool:

ALTER TABLE employees RENAME TO staff;

When you run this command, Oracle will change the name of the table from "employees" to "staff".

  1. Renaming table names and constraint names

In Oracle, renaming a table name not only changes the name of the table itself, but also changes the names of the constraints in the table. This means that if you have foreign key constraints, primary key constraints, unique constraints, or other types of constraints in your table, the names of these constraints will also be modified.

For example, if we have a table named "employees" which contains a primary key constraint named "employees_pk" and now we want to change the table name to "staff", then we need to run the following command :

ALTER TABLE employees RENAME TO staff;

After running, check the constraint name again. You will find that the "employees_pk" constraint name has also been modified to "staff_pk".

If you don’t want to change the constraint name, you can use the following syntax:

ALTER TABLE old_table_name RENAME CONSTRAINT old_constraint_name TO new_constraint_name;

Where, "old_table_name" is the table name, "old_constraint_name" is the constraint name to be modified, and "new_constraint_name" is the new The constraint name.

  1. Notes on modifying the table name

Modifying the table name is not a simple operation because it involves many aspects. Here are some notes:

  • If the name of your table is used in other programs or scripts, be sure to modify all related scripts and programs before modifying the table name.
  • If you need to use a partitioned table in Oracle, then you cannot just use the above ALTER TABLE syntax to modify the table name. Partitioned tables need to be created using the PARTITION keyword, which means you need to use the following syntax:

    ALTER TABLE old_table_name RENAME TO new_table_name UPDATE GLOBAL INDEXES;

    In this command, "UPDATE GLOBAL INDEXES" means to update all global indexes. This is because in a partitioned table, Oracle will automatically create a global index for the index in each partition to ensure data consistency. If you do not update the global index, any queries against the partitioned table may fail.

  • If you have triggers or stored procedures in your table, be sure to modify the code related to these triggers or stored procedures before modifying the table name.
  • Modifying the table name may also affect the relationship between other tables in the database. For example, if your table has foreign key constraints, changing the table name may affect other tables.
  • Be sure to back up the data before modifying the table name. This ensures that if any error occurs, you can easily recover your data.
  1. Conclusion

Modifying table names in Oracle database is a common operation. Although doing so is not irreversible, you must be careful. Before starting any modifications, make sure you have backed up your data and modified other related programs, scripts, and code. If these considerations are taken care of, changing the table name is a fairly simple task.

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